Brake control means



Sept. 30, 1941. D, L'MONEAL E'rAL 2,257,308

BRAKE CONTROL MEANS Filed Nov. 50, 1939 3 Sheets-Sheet 1 INVENTORS DONALD L. McNEAL JOHN CANETTA BY A W14 'IM :ATTORNEY Sept. 30, 1941. D. L. McNEAL ETAL BRAKE CONTROL MEANS 3 Sheets-Sheet 2 Filed Nov. 30,. 1959 INVENTORS DONALD L. McNEAL 8 @N a :3 E 5: v 8 mm H m n 3 5 NT Tww JOHN CANETTA ATTORNEY Sept, 30, 1941. D. L. M NEAL ETYAL 2,257,308 Q BRAKE CONTROL'MEANS v Filed Nov. 30, 1959 3' Sheets-Sheet; 3

45a HX 35,-

INVENTORS DONALD L. McNEAL JOHN CANETTA BY I o Wy ATTORN EY Patented Sept. 30, 1941 2,257,308 BRAKE CONTROL MEANS Donald L. McNeal and John Canetta, Wilkinsburg, Pa., assignors to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application November 30, 1939,'Serial No. 306,878

19 Claims. (Cl. 303-21) This invention relates to brake control means for vehicles, such as railway cars and trains, and has particular relation to brake control equipment, in which the degree of application of the brakes is automatically reduced as the speed of the: vehicle reduces as well as to brake control equipment in which the brakes are automatically released when a vehicle wheel or pair of wheels begins to slip to prevent sliding of the vehicle wheels.

Various types of equipment have been proposed for effecting automatically a reduction in the degreeof application of the brakes as the speed of a vehicle reduces. Various types of apparatus have also been proposed for effecting a rapid reduction in thedegree of application of the brakes when an individual wheel orpair of wheels begins to slip and thereafter effecting reapplica tion of the brakes when the slipping wheel accelerates back toward a speed corresponding to vehicle speed or after the slipping wheel has returned to a speed corresponding to vehicle speed. It has also, been proposed to provide equipment including a combination of speed-controlled and slip-controlled apparatus.

. It is an object of our invention to provide a novel brake control apparatus adapted to automatically reduce the degree of application of the brakes as the speed of the vehicle reduces and at the same time, being adapted to eifectautomatically a rapid reduction in the degree of application of the brakes when a vehicle wheel or pair of wheels begins to slip so as to prevent sliding thereof.

. The above object, and other more specific objects which will be made apparent hereinafter, are attained by means of several embodiments of our invention subsequently to be described and shown in the accompanying drawing, wherein 1 is a simplified diagrammatic view, showing one embodiment of a brake control apparatus for a railway car,

Fig. 2 is a simplified wiring diagram, showing the manner in which the sanding operation in the apparatus of Fig. 1 may be controlled in accordance with the direction of travel by the car,

Fig. ,3 is a fragmental diagrammatic view, showing a modification of the apparatus shown in Fig n1, I

Fig. 4-. is a fragmental diagrammatic. view, showing another modification of the apparatus of Fig. 1, and

Fig. 5 is a, fragmental diagrammatic View,

showing a further modification of theapparatus OfFig L w i Description of embodiment shown in Fig. 1

The brake control apparatus of Fig. 1 is illustrated as applied to a railway car having two four-wheel trucks, the one at the front end of the car being designated hereafter as the front wheel truck H and the one at the rear end being designated as rear wheel truck I 2. It will be understood that each wheel truck has a leading. and a trailing axle and that each axle has fixed to the opposite ends thereof a car wheel I3 which rolls on a corresponding rail of the track designated by the reference numeral l5. For simplicity, only one wheel is shown for each axle.

Conventional brak devices, such as brake shoes, are associated with each of the wheels I3 in manner not shown and operated by brake cylinders [6 through brake rigging also not shown. In Fig. 1, a brake cylinder [6 is provided for operating the brakes associated with the wheels of each axle but it will be understood that. an individual brake cylinder may be provided for operating the brakes associated with each wheel or a single brake cylinder may be employed for applying the brakes associated with, all the wheels of a wheel truck.

The apparatus for controlling the pressure in the brake cylinders I6 is illustratively shown as comprising two train pipes, referred to herein-,- after as the supply pipe I! and the control pipe I8, respectively, a reservoir I9 hereinafter referred to as the main reservoir and charged with fluid under pressure by a fluid compressor, not shown, a manually operated brake valve device 2| of the self-lapping type for controlling the pressure in the control pipe I8, a speed-controlled valve mechanism 24, a slip-controlled valve mechanism 25, a pressure-operated switch 26 controlled accordingto the pressure in the control pipe 18, and apressure-operated switch 21 for each wheel truck adapted to be controlled according to the pressure in the corresponding brake cylinders.

The apparatus further includes a plurality of sanding devices 2 Elf and 292" of conventional type. Two sanding devices 291 are provided for each wheel truck II and I2 for causing deposition of sand in advance of the vehicle wheels 13, upon the supply of fluid under pressure thereto, when i the car is traveling in a forward direction. Similarly, two sanding devices 291- are provided for each wheel truck for causing deposition of sand in advance of the vehicle wheels [3 when the car travels in the reverse direction.

Fluid under pressure is supplied to the sanding ply pipe I! and is effective close the charging communication and open the communication through which fluid under pres-, sure is supplied from the reservoir 3| to the sand a valve ,device 32.

V of the corresponding long" as the 'Wl'iGBlS on'the leading axle "of the devices 29 and 2% from acorresponding sanding reservoir 3! for each wheel truck under the control of a magnet valve, device 32 of the double beat type. The magnet valve device 32 is effective when deenergized to establish a communication through which the sanding reservoir 31 is charged with fluid under pressure from the supwhen energized to ing devices to efiect sanding,

The supply of fluid under pressure to the sanding devices 2%; for each wheel truck is also controlled by a valve ZBaoi the solenoid-operated type which is interposed between the magnet valve 32 and the sanding devices. Similarly, the supply of fluid under pressure to the sanding devices 291- of each wheel truck is controlled by a solenoid operated valve 2% which is interposed between the magnet valve 32 devices. As shown in Fig.2, the solenoid windings 'of the valves 29a for the two wheel trucks are connected in parallel relation and the solenoid windings of the valves 29b for'both wheel trucks .are connected in parallel relation. The solenoidwindingsfor valves 29a. and 29b are alternatively energized orrdeenergized under the control of a suitableswitchZS, either manual or automatic in character, of the single-pole double throw type by currentsupplied from a suitable battery 49. 3

and the sanding .7 The solenoid-operatedvalves are adapted to be wopenwhen the solenoid windings thereof is deenergiz ed and closed when the solenoid winding is'energizedr Thus, when the car-istraveling in .a forward direction, the blade of the switch '28 is thrown to its lower position, as shown, to .efiect energization of only the solenoid windingsoi the valves 2% andconsequent closure thereof. Accordingly, when .the magnet valve 32 is. energized, fluid under pressure is supplied :only to the sanding devices 29f through ,the open-valves 29a. traveling in a reverse direction, thezblade of, the switch-28 .is thrown to .its upper position thereby causing energization of only thesolenoid winde ings-of the valves 29a and the consequentrclosure thereof. In such case, whenmagnet valve 32. is

energized, .fiuid under pressure is supplied nly to the sanding devices 2912 1 Associated .witheach sanding reservoir is a pressure-operated switch .33 which controlsthe energizing circuit of the corresponding magnet :Each pressure-operated switch 33 .is adapted to open when the pressure in the corresponding sanding reservoir 3! reduces by exhaust through the sandinjgfdevices 2.91 or 291 below a certain low pressure. H i a .The apparatus further includes a generator .35,

of the direct-cur'rent'type, for each axle of each @wheel truck, each generator beingarrangedto be driven according to the speedof rotation of the corresponding axle as; 'for example, by be-. ing mounted in. the journal housing at o11e' .end

of the axle, with the armature. shaft of the generatorfcoupled to "the end of the axle. The 'g'eneratorsftt areso designedas to proe v ducei a "direct-current voltage 'at the brusl'r'ter inals there'oi which 'is substantially proportional to the 'sp-eedpf rotation of 'the corresponding axle and wheel fixed thereto and which is of op Conversely, .when the car is terminals of the generator 35 associated with the leading axle of the front wheel truck II are three voltage-responsive relays 36, 31 and 38, re-

spectively. These three relays are designed to pick-up and drop-out at different voltages corresponding. to different speeds of travel of the car. Thus, the relay 36 is adapted to operatively respond or pick-up only at a voltage exceeding that corresponding substantially to a 20 mile per hour speed of travel of the car, relay 31 is adapted to pick-up only at a voltage exceeding that corresponding to a 40 mile per hour speed of travel of'the car, and relay 38 is adapted to pickup only at a voltage exceeding that corresponding to a mile per hour speed of travel of-the The relay 36 has asingleback-contactmember a which is in closed position when the relay is not picked-up and which is operated to open position when the relay is picked-up. Each of the relays 3i and 38 has two contact members a and b respectively. The contact member a of each of the relays 3! and 38 is a front-contact member which is in open position when the relay is not picked-up and which isoperated to-aclosed position when the relay is picked-up. -'-I-he contact member -b' of eachfof the relay 31 and-38 of the double-contact type and occupies alower cl'osedposition when the relay is dropped-outand an upper closed "position when "the relay is picked-up. r

As will beseen in the drawings, one-terminal-of the operating coilof relay 35 is connected to the wire 30 while the other is connected to'the-wire the wire 30 whereas the other terminal of the operating coil is connected to the'wire 20 under the control of the contact member I) of the relay 38. The terminals of the operatingcoilof the relay 38 are connected directly across the tw wires 20 and 3t]. I l

The contact member I) of the relay 3'! is eifective, in its upper closed position, to include'a current-limiting device, such as a resistor Mjbetween the one terminal'of the operating coil" of relay 36 and the wire 20. In a similar manner the contact member -b-of relay -38 is effective, in

its upper closed positiomto include a similar-resister Al between the one'terminal of the'operat ing coil of relay 3? and *the-Wire-Zfi. Inthelower closed positions thereof, thecontact members b of the relays-31 and 38 connectthezoneterminal of relay 36 and relay 3'! respectively directly-to wire 30, thus cutting the resistors 4l -o ut of 'the circuit. 7

It will thus-be seenthat when the relay -31 is picked-up; a resistor 41 limits the current through the operating coil of relay 36. In a similar manner, When the relay 38 is picked-up, the

' corresponding resistor 4| limits the 'curren-t positeipolarity for'opposite directions of rotation wheels. Accordingly, "as

through the operating coil of the relay =37; -'Ihe purpose of the resistors 4| is to prevent theburning-out of the operating ;coils of relays Stand 31 when the voltage across the brush 'termin-ais of the' gen-erator 35 reaches the high -value occurring at high speeds in excess of 65 M. Pl-I; The coil of relay 38 does not require such protec-z whenever the impressed voltage exceeds the predetermined pick-up voltage regardless of its polarity'and, therefore, of the direction of travel of the car.

Each of the generators 35, including the generator 35 associated with the leading axle of the front wheel truck II, has connected across the brush terminals thereof, in series relation, an electrical condenser 42 and a current-responsive relay 43. The relays 43 are of the neutral type adapted to pick-up whenever the current flowing through the Operating coil thereof exceeds a certain value, regardless of the direction of flow of current and consequently the direction of travel of the car. The arrangement of the condenser 42 and current-responsive relay 43 in each generator circuit is such as to cause a flow of current in the circuit proportional to the rate of change of voltage at the brush terminals of the generator and consequently to the rate of accelerationor deceleration of the corresponding vehicle wheels. It will be observed that upon acceleration of the car, the voltage at the brush terminals of each generator increases at a corresponding rate to effect charging of the electrical condenser, the current flow in the circuit being proportional to the rate of increase of voltage at the brush terminals of the generator. Conversely, when the car wheels decelerate and the voltage at the brush terminals of the generator reduces at a corresponding rate, the current discharged from the condenser 42 is substantially proportional to the rate of reduction of voltage atthe brush terminals of the generator. It should be understood that the arrangement of the relay 43 and condenser 42 to measure the, rate of change of rotative speed of the vehicle wheel is not, per se, our invention.

- The current-responsive relays'43 are so designed as to pick-up only in response to a current exceeding a certainvalue and corresponding to a certain rate of deceleration or acceleration of the vehicle wheels, such as ten miles per hour per second.

It is well known that such a high rate of deceleration of the vehicle wheel is not attained unless the vehiclewheels slip. The term slip, asemployed herein, designates the rotation of a vehiclewheel at a speed less than a speed corresponding to vehicle speed and resulting from application of the brakes to a degree sufiicient toexceed the adhesion between the wheel and the rail. Once a vehicle wheel starts to slip it decelerates rapidly at a rate exceeding ten miles per hour per second to a locked-wheel condition. The term slide, as employed herein, designates the dragging of the vehicle wheel along a road surface or rail in a locked condition, as

picked-up and which is operated to a closed position when the relay is picked-up. 1 a i The contact members of the relays 43 corresponding to the axles of the front wheel truck II are connected in parallel relation in such a manner that either of the two relays is effective,

when picked-up during an application of the brakes to effect energization of a sand relay 45 and a brake relay 46,

In a similar manner, the contact members of the current-responsive relays 43 for the axles of the rear wheel truck l2 are connected in parallel relation in such manner that either is efiective when picked-up during an application of the brakes to effect energization of a similar sand relay 45 and brake relay 46 for the rear wheel truck.

The relays 45 and 46 are of the neutral type, each having a single front-contact member which is actuated from an open to a closed position when the relay coil is energized. As will be made apparent hereinafter, the contact members of the relays 45 and 46 are self-holding contact mem-- bers; that is, they are effective once actuated to closed position to continue to establish a holding circuit for maintaining the operating coil of its relay energized thereafter independently of the relays 43.

The sand relay 45 for each wheel truck is effective when picked-up to cause energization of the corresponding sanding magnet Valve device 32. The brake relay 46 for each wheel truck is effective when picked-up to cause operation of the slip-controlled valve mechanism 25 to cause a rapid release of the brakes on the corresponding truck. a

, Before describing the operation of'the equip-,- ment, a brief description ofthe brake valve device 2!, the speed-controlled valve mechanism 24, and the slip-controlled Valve mechanism 25 will be given. a

The brake valve device 2| is of the type described and claimed in Patent 2,042,112 of Ewing K. Lynn and Rankin J. Bush. Briefly, it comprises an operating handle 22 for operatively moving a rotary operating shaft of a self-lapping valve mechanism. In the normal release position of the brake valv-e handle 22, the self lapping valve mechanism of the brake valve device is conditioned to vent the control pipe l8 to atmosphere through the exhaust port 23 thereof. When the brake valve handle is shifted out of its release position into a zone, referred to as the application .zone, the self-lapping valve mechanism is operative to supply fluid under pressure to the control pipe I3 from the supply pipell. Supply pipe I1 is constantly connected to main reservoir l9 and charged to the pressure therein. The self-lapping valve mechanism is so designed as to establish a pressure in the control pipe l8 corresponding to the degree of displacement of the brake Valve handle 22 out of its release position. Thus, if the pressure in the of the type described and claimed in Patent 2,140,624 of E. ELHewitt. Briefly it comprises aselfelapping relay valve section 5 I, a diaphragm section .52 comprising a plurality of coaxially spaced movable abutments or diaphragms of different effectivepressure areas respectively, and a magnet valve section 53including a so-called high magnet valve .54, a medium magnet valve 55 and a low magnet valve 56.

The magnet valves 54, 55 and 56 respectively controlthesupplyof fluid under pressure to and the release of fluid under pressure from a corresponding one of the chambers formed in the diaphragm section 52 between successive diaphragmsand thus due to the difference in area of the diaphragm control the operating pressure r diaphragms .of thevalve mechanism 24 under the :control .of the magnet valve 54 and 55 and 5B is from a branch pipe 9| of the control pipe 18, so that the pressure of the fluid supplied to the valve mechanisms 25 also varies in proportion to the pressure established in the control 7 pipe.

:The arrangement of themagnet valves 54,55 and 56 is, such that'when the low magnet valve 55 onlyiis energized, the pressure from the control pipe 48 is effective on the smallest diaphragm only and accordingly the pressure supplied by the relay valve mechanism in section 5| of the valve mechanism 24 bears a minimum ratio to thepressure established in the control pipe I8.

When all of themagnet valve devices 54, 55 and 5B are deenergized, fluid under pressure is supplied from the control pipe l8 to act on the smallest diaphragm and the next larger diaphragm so that the relay valve mechanism in section 5! of the valve mechanism 24 correspondingly operates'to deliver a higher pressure for the same control pipe pressure.

When only the medium magnet valve device 55 is energized, fluid under pressure is supplied from the control pipe l8 to then act on the smallest diaphragm and the next two larger diaphragms so thatthe relay valve mechanism in section'5l of the valve mechanism 24 correspondingly operates to supply fluid at a still higher pressure for a given control pipe pressure. I .When the high magnet valve 54 and the mediummagnetvalve 55 are energized and the low magnet valve'disdeenergized, fluidunder pressure .issupplied from the control pipe 18 to act' mechanism of valve mechanism ,24 and that established in the control pipe I8 will correspondingly vary.. For illustrative purposes it will be assumed that when the lowmagnet valve 56 only is energized, the pressure of the fluid de livered by the valve mechanism 24 to the slip controlled valve mechanisms 25 isone-third of that es a lis d in me contrb p Inmate further assumed that when all the magnet valve devices 54, :55, and. 56 are deenergized, thepressure of the fluid delivered to theslip-controlled valvemechanisms 25 is one-half of the pressure established in the control pipe. When only the medium magnet valve 55 is energized, it is assumed that the pressure of the fluid delivered to the slip-controlled valve mechanisms 25 ;is

threefourths of the pressure established in the control pipe. Whenthe high magnet valve 54 and the medium magnet valve 55 are both energized while the low magnet valve 56 is deenergized, the pressure delivered to the slip-controlled valve mechanisms'25 by the valve mechanism 25 is;assumed to be substantially equalto the pressure established in the control pipe.

The slip-controlled valve mechanism 25 for eachwheel truck is of the typedescribed indetail and claimed in Patent 2,218,619 to Donald L. McNeal, one of the present jointapplicants. Since reference may be had to the patent just mentioned for details of construction of the valve l'nfichanism 25, a brief functional descrip: tion only is given herein.

Each valve mechanism v25 comprises a relay valve, portion ,6! and a magnet valve portion 62 secured to opposite faces respectively of an intermediate pipe bracket section 63. The relay valve portion ,6! comprises a self-lapping valve mechanism which has an operating piston that is subject on one face thereof to the pressure of fluid delivered from the speed-controlled valve mechanism 24. The relay valve portion of each of the valve mechanisms 25 is operative according to the pressure delivered to the operating' piston thereof for supplying fluid at a corresponding pressure to the brake cylinders l6 asso ciated therewith.

The magnet valve portion 62 of each valvemechanism 25 includesa magnet valve device 55. The magnet valve device 55 is effective, when de-. energized, to permit the flow offluid under pressure from the supply pipe 64 to the operating piston of the relay valve portion 5! and, when energized, to cut off ,suchsupply and to rapidly portion 5i to'be restricted to a rate lower'than the normal rate, as long as the pressure inthe pipe 54 exceeds a certain low pressure such as five pounds per square inch.

It will be further noted that the source of fluid under pressure for the speed controlled valve mechanism '24, the slip-controlled valve mechanism 2 5 and the sanding reservoir 3i is the s up-.

ply pipe H. The relay valve portion5l of the speed-controlled valve mechanism 24 is connected'to the supply pipe I! by a pipe 53 and a branch pipe 57. A second branch 58 of th pipe fifi leads to the pipe bracket section 53 of the-slip-controlled valve mechanisms 25 for both wheel trucks; Also, two branch pipes '65 of the pipe 68 lead respectively to the two sanding mag-'- net valves 32 which in turn respectively control the supply of fluid under pressure to the sand:

ing reservoirs 3|.

Operation of equipment shown in Fig. 1

Let it be further assumed that the car is at.

a standstill and that the brake valve handle 22 is in its release position so that the control pipe I8 is correspondingly at atmospheric pressure.

As will be seen hereinafter, fluid under pressure is accordingly exhausted from the brake cylinders l6 so that the brakes are released. At the same time the pressure-operated switches 26 and 21 are in open position as shown.

Since the car is at a standstill, the generator 35 associated with the leading axle of the front wheel truck H is not producing a voltage and therefore no voltage is impressed on the wires 26 and 30. 31, and 38 are, therefore, all dropped-out. In its dropped-out position, the back-contact member atof the relay 36 establishes a circuit for energizing the magnet winding of thelow magnet valve 56 of the speed-controlled valve mechanism 24. V This circuit extends from one terminal, such as the positive terminal, of a suitable battery H, by way of a wire 12 including a manually operated knife switch 13,: contact member, a of the relay 36, a wire 14, the magnet winding of the low'magnet valve 56, and wires 15 and "back to the negative terminal of the battery H. The front-contact members a of the two relays 31 and 38 are each in open position and the high and medium magnet valves 54 and 55 are thus deenergized.

It will thus be seen that the speed-controlled valve mechanism 24 is conditioned so that upon the charging of the control pipe l8, the pressure delivered by valve mechanism 24 through the pipe 64 to the operating piston of the relay valve portion 6| of each slip-controlled valve mechanism 25 bears a minimum ratio to the pressure established in the control pipe. As. previously assumed, the pressure established in the pipe 64 under the assumed condition will be one-third of the pressure established inthe control pipe. Let it now be assumed that with the brake valve handle 22 remaining in its release position. the operator operates a suitable power controller, not shown, to start the car in the forward direction, indicated by the arrow as movement in the left-hand direction. Let it also be assumed that the operator has previously shifted the blade of switch 28 to the position shown in Fig. 2 so that the solenoid valves 29b are closed and the solenoid valves 29a are open. As the The voltage-responsive relays 36,

speed of the car increases, the voltage at the brush terminals of the generator 35 associated with each axle correspondingly increases. When the voltage at the brush terminals of the generator 35associated with the leading axle of the front wheel truck exceeds a value corresponding to a speed of 20 M. P. H. travel of the car, the relay 36 is picked-up. The contact member a of the relay 36 is accordingly actuated to its open above 40 M. P. H. the corresponding voltage at the brush terminals of the generator 35 for the leading axle of the front wheel truck causes the relay 3'! to be picked-up. The front-contact member a of the relay 3'! is accordingly actuated to its closed position and thereby establishes a circuit for energizing the magnet winding of the medium magnet valve 55 of the speed-controlled valve mechanism 24. This circuit extends'from the positive terminal of the battery H through the wire 12 including the switch 13, contact member a of the relay 31-, a wire 18, the magnet winding of the medium magnet valve 55, a wire 19, and wire 16 back to the negative terminal of the battery 7 I i The contact member 27 of the relay 3! is effective in its picked-up position to insert the resistor 4! in series with the operating coil of the relay .36 across the wires 20 and 30 for the purpose previously explained. The current energizing relay 36 is thus reduced but not enough to cause relay 35 to drop-out. i a i .Let it be assumed that the .speed of the car increases further to a speed in excess of .65 M. P. H. In suchcas-e the. voltage at the brush terminals of generator 35 associated with the leading axle of the front-wheel truck ll causes relay 38 to be picked-up. The contact member a of the relay 38 is efiective in its picked-up position to establish a circuit for energizingthe magnet winding of the high magnet valve 54 of the, valve mechanism 24. This circuit extends from the positive terminal of the battery H by way of thewire 12 including the switch 13, contact member a. of the relay 38, a wire '8l, the magnet winding of the high magnet valve 54, a wire 82, and wire 16 back to the negative ter-- minal of the battery I I.

Thecontact member I) of relay 38 is effective inits picked-up position to insert the resistor 4| in series with the operating coil of relay 3'! across the wires 20 and 30. for the purpose previously. explained. The current-energizing relay 31 is thus reduced but not enough to cause relay 3! to drop-out.

, It will be thus as. that the magnet valves 54, 55, and 56 of the valve mechanism 24 are selectively energized or deenergized in different combinations depending upon the speed of travel of the can f Now let it be assumed that while the car is traveling at a speed, in excess of M. P. H.:

the operator desiresfto effect an application of the brakes. To do so the operator shuts oif the propulsion power, if the power is on, and shifts the brake valve handle 22 out of its normal release position to a position corresponding to the desired degree of application of the brakes. The control pipe 18 is accordingly charged to a pressure for example, such as 60 pounds per square inch. Fluid under pressure is accordingly supplied from the control pipe (8 by way of branch pipe 9| to the chambers associated with all 01' position. The magnet winding of the low mag get valve 56 of the speed-controlled valve mechanism 24 is accordingly deenergized by interruption of its energizing circuit. 3 When the speed of travel of the car increases the diaphragms of the speed-controlled valve mechanism 24 due to the fact that the magnet valves 54 and 55 are energizedand themagnet 55 is deenergized. The relay valve portion 5| of the valve mechanism 24 is accordingly operated to 'supply'fluid, at a pressure substantially equal to the pressure established in the control pipe, to the pipe 64 leading to the operating piston chamber of the relay valve portion 6! 01 the slip-controlled valve mechanism 25 for each wheel truck.

The relay valve portion 6! of the valve mechaof the relay 31.

nism 25 for each wheel truckis accordingly op erated to supply fluid under pressure from the supply pipe'BB to the brake cylinders I6 to establish 'a pressure therein substantially equal to the pressure established in the control pipe I8. The car is accordingly decelerated in response to the application of the brakes and the speed of the car, therefore,correspondingly reduces.

As is we1l known, it is an inherent characteristic of conventional relays that the contact members thereof do not drop-out in response to a decrease of impressed voltage or energizing current at the same value of impressed voltage or energizing current that caused the relay contact members to be picked-up because of the fact that, once the armature of the relay is picked-up, the air gap between the armature and the magnetic core is reduced. Thus, the voltage responsive relay 38 does not drop-out-immediately upon the reduction of the car speed below 65 M. P. H. but drops out at some value slightly below 65 M .P. H. such as 60.M. P. 1-1. When the speed of travel of the car is reduced sufficiently to cause the relay 38 to drop-out, the contact member a or relay 33 is returned to open position to interrupt the energizing circuit of the magnet winding of the magnet .valve 54 and the contact member b of the relay 38 cuts the resistor 4I out of the circuit of the operating coil With only the medium magnet valve 55 of the valve mechanism 24 energized, the relay valve portion 5I of the valve mechanism 24 is operated to effect a reductionof the pressure in the pipe 64 leadingto the slip-controlled valve mechanisms 25 without any reduction of the pressure in the control pipe I8. As previously explained,

the pressure established in the pipe 64 with only i the magnet valve 55 of the valve mechanism 24 energized is three-fourths of the pressure established in the control pipe I8. Accordingly, assuming 60 pounds per square inch pressure to be maintained in the control pipe I8, it. will be seen that upon the drop-out of the relay 38,.the pressure of the fluid supplied to the relay valve portion 6| of the control valve mechanisms 25 is reduced to pounds per square inch.

. Upon such reduction of the fluid pressureoperating the relay valve portion SI of each valve mechanism 25, the relay valve. portion 6| operates to reduce the pressure in the brake cylinders to 45 pounds. per square inch, thereby corre- 'spondingly decreasing the degree of application of the brakes. v

When the speed of the car reduces sufiiciently to cause drop-out of the relay 31, and such dropout occurs when the speed reduces somewhat below 40 M. P. the contact members a and b of the relay 3'! are returned to their droppedout positions respectively interrupting the energizing circuit for the medium magnet valve 55 and cutting-out the resistor 4I from'the'circuit of the operating coil of the relay 36.

With all of themagnet valves 54, 55, and 56 of the. valve mechanism 24 now deenergized, the relay valve portion 5I of the valve mechanism 2.4 is operated to further'reduce the pressure in the pipe 64 to a value which isone-halftlie pressure established in the control pipe I8. Assuming, a pressure of 60 pounds per square inch to be maintained inthe control pipe, the pressure in the pipe 64' is accordingly reduced to'30 pounds per square inch. The relay valve portion 6| ofthe valve mechanism 25 for each wheel truck is accordingly operated to effect a corresponding reduction of pressure in the brake cylinder to 30 pounds per square inch, thereby further decreasing the degree of application of the brakes.

As the speedof travel of the car further reduces, due to the application of the brakes, to a value somewhat below 20 M. P; H., the relay 36 is dropped-out. Contact member a of the relay 35 is accordingly effective in its dropped-out position to establish the circuit for energizing the magnet winding of the magnet valve 56. The relay valve portion 5I of the valve mechanism 24 is accordingly operated to reduce the pressure in the pipe 64 to one-third of the pressure estab lished in the control pipe I8. Assuming the pressure of 60 pounds per square 'inch to be maintained in the control pipe I8, the pressure in the pipe 64 is accordingly reduced to 20 pounds per square inch. The relay valve portion 5I of the valve mechanism 25 for each wheel truck is accordingly operated to reduce the pressure in the brake cylinders 16 to 20 pounds per 7 square inch. 7

-As the speed of the car further reduces and the car approaches a stop, the degree of application corresponding to the last described condition of the valve mechanism 24 remains in effeet. It will be apparent, however, that if in accordance with the usual'manner of operation, the operator shifts thebrake valve handle 22' back toward the release position to reduce the pressure in the control pipe I8 as the car ap-- proaches a stop, the pressure in the brake cyl.- lnders is likewise correspondingly reduced. The ratio between the pressure in the brake cylinders and the pressure established in the control pipe I8 is, however, at all times dependent upon the condition of the valve mechanism '24 as determined by energization or deenergization 'of the magnet valves-54, 55- and 56.

The automatic reduction in the degree of application of the-brakes in response to the reduc-'- tion in the speed of travel of the caris adapted under normal conditions to prevent such excessive application of the brakes as will result in theslipping of the vehicle wheels. If,"however, due to. abnormally 0r unusually poor adhesion between the wheels and the rails,'a vehicle wheel should beginto slip during an application of the -brakes, a further operation'of the equipment occurs whichwill now be described:

Let it be assumed that during an application of the brakes, the wheels on the trailing axle of the front wheel truck II begin to slip. The relay 43 in the. circuit of the generator 35 associated with suchaxle is accordingly pickedup due to the wheel decelerating at a rate in excess of the value sufiicient to cause pick-up of. the relay. When the relay 43 is picked-up,

the contact member thereof is actuated to closed position and thereby establishes a circuit for energizing the operating coils of the relays 45 and 46 for the front wheel truck. This cir-' cuit extends from the positive terminal of the battery II by way of wire I2, a branch wire including a switch 96, such as the knife switch shown, and the pressure switch 26, a wire 91, the contact member of the relay 43 for the trailing axle .of .the front wheel truck H, wires 98 and 99 to a wire HM, and then through two parallel bran-ch circuits. The one branch circuit extends from the wire IiJI through the operating coil of therelay 45, a wire I52, pressure switch 33. a wire I03, the magnet winding of the sanding magnet valve 32, a wire I04, and wire 16 back to the negative terminal of the battery 1!.

The other branch circuit extends from the wire I (H through the operating coil of the relay 46, a wire I06, pressure switch 21, -a wire I01, the magnet Winding of the magnet valve device 65 for the valve mechanism 25 corresponding to the front wheel truck H, a wire I08, and wires I04 and 16 back to the negative terminal of the battery 1|.

The contact members of the two relays 45 and 46 are actuated to closed position in response to energization of the relays to establish self-holding circuits for their respective relays. It will be apparent that such is the case because the contact members of the relays 45 and 43 are effective, when in closed position, to establish a connection between the wire 95 and the wire llil in parallel relation to the contact members of the corresponding current responsive relays 43. Thus, once the relays 45 and 46 are picked-up, they remain picked-up thereafter until the holding circuittherefor is interrupted in the manner subsequently to be described, independently of the condition of the relay 43.

Upon energization of the magnet winding of the sanding magnet valve 32, fluid under pressure is accordingly supplied from the sanding reservoir 3| to the sanding devices 29f for the front wheel truck ll. Since the solenoid operated valve 29a is open and the solenoid operated valve 291) is closed, as previously assumed, it will be apparent that fluid under pressure is supplied to the sanding devices 29f only and not to the sanding devices 29r. Thus sand is deposited only in advance of the car wheels l3 while the car travels in a forward direction.

Upon energization of the magnet winding of the magnet valve device 65 of the valve mechanism 25, the supply of fluid under pressure from pipe 64 to the operating piston of relay valve portion 6| is cut oil and fluid under pressure is vented therefrom at a rapid rate. The relay valve portion is accordingly operated to effect a corresponding rapid reduction of the pressure in the brake cylinders 26 for the front wheel truck II.

The sanding operation and the automatic re lease of the brakes, it will be observed, occurs only on the wheel truck having a slipping wheel. Thus, if no wheels on the rear wheel truck I2 slip, the automatic sanding and brake release does not occur on the rear wheel truck. If one or more wheels on the rear wheel truck slip, the automatic sanding and brake release is effected in a manner similar to that described for the front wheel truck.

The sanding operation and the reduction of the pressure in the brake cylinder continue until such'time as the pressure switches 33 and 21 respectively are operated to open position. The rate of reduction of the pressure in the sanding reservoir 3| by exhaust of fluid under pressure therefrom through the sanding devices 29 is so controlled that the pressure acting to maintain the pressure switch 33 closed does not reduce sufficiently to open the pressure switch 33 until after a certain interval of time, such as ten or fifteen seconds, elapses. The pressure switch 21 associated with the brake cylinders I6 is not operated to open position until the pressure in the brake cylinders reduces below a certain low pressure, such as ten pounds per square inch, whichis sufficientlylow to insure the cessation of deceleration of the slipping wheel and the acceleration thereof back to a speed corresponding to vehicle speed.

When the slipping wheel ceases to decelerate because of the reduced brake cylinder pressure and begins to accelerate back toward a speed corresponding to vehicle speed, the rate of acceleration of the vehicle. wheel is such as to cause the corresponding current-responsive relay 43 to be picked-up after a momentary drop-out thereof during the transition from deceleration to acceleration. As previously stated however, such operation of the current-responsive relay 43 is without effect in view of the holding circuits established by the relays 45 and 46. Furthermore, the time required for the pressure in the brake cylinders of the front wheel truckto reduce sufficiently to open the corresponding pressure switch 21 is-of such length that the slipping wheel will have returned previously to a speed corresponding to vehicle speed.

Upon the opening of the pressure switch 33, the holding circuit for the sanding magnet valve 32 is interrupted,'thereby deenergizing theimag net valve 32 and the relay45. The sanding operation is accordingly terminated and the recharging of the sanding reservoir 3| is immediately effected. When the pressure switch 33 recloses in response to the recharging of the sand: ing reservoir 3! to its normal pressure, the sand ing magnet valve 32 is not again energized because the contact memberlof the relay 45 is in open position. It will be apparent, moreover, that, due to the fact that the slipping wheel or Wheels have returned to a speed corresponding to vehicle speed before pressureswitch 33 recloses, the current-responsive relay 43 corresponding to the slipping wheel will also be in its dropped-out position and consequently the relay 45 and magnet valve 32 will not be energized again when the pressure switch 33 closes.

Upon the opening of the pressure switch 21, the holding circuit for the relay46 is interrupted and the magnet winding of the magnet valve device 65 is deenergized. The magnet valve portion 62 of the valve mechanism 25 accordingly becomes effective to cause the resupply of fluid under pressure from the pipe 54 to the operating piston of the relay valve portion 6| of the valve mech anism 25 at a restricted rate. The relay valve portion 6| is accordingly operated to restore the pressure in the brake cylinders l6 of the front Wheel truck at arestricted rate.

Due to sanding and due also to the restoration of brake cylinder pressure at a restricted rate, the possibility of repeated slipping of any of the wheels on the same truck is minimized. If, however, any of the wheels on the truck should begin to slip againafter the brakes have been reapplied, the corresponding relay 43 is again picked-up and the sanding, brake release, and brake application operation previously described is repeated.

If the wheels on the leading axle of the front wheel truck ll begin to slip, the voltage at the brush terminals of the corresponding generator 35 and impressed on the voltage-responsive relays 36, 31, and 38 correspondingly reduces. In such case, therefore, the magnet valves 54, 55and 56 will be correspondingly controlled so as to in some cases reduce the ratio between the pressure established in the pipe 64 leading to the slipcontrolled valve mechanism 25 of both wheel trucks and the pressure establishe in the con trol pipe l8.

- In such cases, therefore, the valve mechanism 25 for the rear wheel truck valve will be operated to correspondingly reduce the pressure in the brake cylinders l6 of the rear wheel truck. However, since the voltage-responsive relays 36, 3?, and 38 will be immediately restored to the proper condition thereof corresponding to the speed of r may occur.

It will be apparent, therefore, that in a train of cars, the brake control equipment on each car isv adapted to functionas an independent unitin respect to the speed-control and slip-control operation thereof. Thus, the only connection, as far as the control of the brakes is concerned, between successive cars in a train is that'established by the usual hose couplings between the sections of the train pipes I! and I8 on the respective cars. 1

After a car or trainhas come to a stop in :response to an application'of the brakes, and the operator desires to release the brakes prior to again starting the car or train, he merely shifts the brake valve handle 22 back to its normal release position. The pressure in the control pipe I8 is accordingly reduced to atmospheric pressure so that the pressure in the chambers associated with the diaphragms of the speed-controlled valve mechanism 24 is correspondingly reduced to atmospheric pressure. The relay valve portion of the valve mechanism 24 on each car is accordingly operated to exhaust fluid under pressure from the operating piston chambers of the relay valve portion 6| of each valve mechanism 25 on each car so that the pressure in the brake cylinders is correspondingly reduced to atmospheric pressure and the brakes thereby completely released.

If I for some reason, such as the failure of the generator associated with the leading axle of the'front wheel truck H, the operator desires to 'cut the speed-controlled valve incchanism out of normal operation he may do so by simply opening the switch 13, thereby preventing energization of any of the magnet valves 54, 55,

and 56 of the speed-controlled valve mechanism 24. In such case, therefore, the pressure established in the brake cylinders will always be onehalf the pressure established in the control pipe 18. If switch 13 were not provided, the failure of the generator 35 on the leading axle of'the front wheel truck would result in drop-out of all the relays 36, 31 and 38 and thus permit only the lowest ratio of the pressure in the brake cylinder to the pressure in the control pipe. Thus since only one-third of the pressure established in the control pipe [8 could be established in the brake cylinders, the degree of application of the brakes possible would be undesirably low.

If the operator desires, or if it is necessary for some reason, to cut the sanding devices 29) and 291? as well as the magnet valve 65 of the valve mechanisms 25 on a car out of operation, the operator may do so merely by opening the switch 96 thereby preventing the energization of the sanding magnet valve 32 and the magnet valve devices 65 of the valve mechanism 25.

If the car is connected in a train in such a manner as to travel in a reverse direction, or if the car is of the double-end type permitting power control and brake control fromopposite' ends of the car the apparatus functions in exactly the same manner as for the forward. direction of travel. It is necessary, however, in the case of the reverse travel of the car, for the operator to throw the blade of switch 28 to the position opposite to that shown in Fig. 2 so as to effect closing of the solenoid-operated valves 2% in the pipes leading to the sanding devices 26] and at the same time to effect opening of the solenoid-operated valves 29b in the p-ipesleading to the sanding devices 291. Thus, when the sanding magnet valves 32 are energized, fluid under pressure is supplied to the sanding devices 267' and not to the sanding devices 29), so that sand is deposited only'in advance of the vehicle wheels for the reverse travel of the car.

It will be apparent that the polarity. of the voltage at the brush terminals of the generators 35 is reversed upon reversal of the direction of travel of the car. Thus, upon the starting of the car in the reverse direction, the voltage impressed on the voltage-responsiverelays 36, 31,. and 38 and the current-responsive relays '43 is.

reversed. However, since these relays always respond to a voltage or current in excess of a oertain predetermined value for each relay, the reversal of polarity in no way changes the operation thereof. It is accordingly deemed unneces sary to further describe the operation of the equipment for the reverse travel of the car.

Embodiment shown in Fig. 3

Fig. 3 shows a fragment of the entire apparatus of 'Fig. 1 including a modified arrangement whereby th voltage responsive relays 36, 31, and 38 pick-up and drop-out at substantially the same speed whether the speed of the car is increasing or decreasing. The remainder of the apparatus, not shown, being the same as in Fig. 1,

, stantially the same speed whether the speed of the car is increasing or decreasing, three additional relays 36A, 31A, and 38A are provided. These relays are respectively effective, when the relays 36, 3'5, and 38 are picked-up to cut a resistor A0 in series relation with'the operating coil of the corresponding relay across the wires 20 and 3!! leading to and connected across the brush terminals of the generator 35 associated with the leading axle .of the front wheel truck H.

The relays 36A, 3'FA, and 38A are of the neu-' tral type, each having a contact member a'which is shifted from a lower closed position, which it occupies when the relay coil is energized, to an upper closed position when th relay coil is energized.

The operating coil of the relays 35A, 31A, and 38A is in series-circuit relation with the magnet winding of the magnet valve devices 56, 55, and 54, respectively, of the speed-controlled valve mechanism 24, being included respectively in se-' ergization of the low magnet valve 56 and deenergization of the medium magnet valve 55 and high magnet valv 54.

When the speed of the car increases above M. P. H. and the relay 36 is picked-up, the coil of therelay 36A and the magnet winding of the magnet valve 56 are simultaneously deenergized. The contact member a of the relay 36A is'efiective in its lower or dropped-out position to cut a corresponding resistor 40 in series relation with the coil of the relay 36. The resistor 49 is of such resistance as to reduce the current through the operating coil of the relay 36, at the time it is picked-up or energized, to a value just suflicient to maintain the relay picked-up. It will thus be apparent that such reductionof current by resistor! compensates for the reduction of the air gap between the armature and the stationary core of relay 36 so that when the gen- 'erator voltage impressed on the wires 20 and reduces, du to a decreasing speed of the car, the relay 36 will be dropped-out at substantially the same speed of the car at which it picked-up.

The contact member a. of relay 31A is effective in its upper or picked-up position to cut a corresponding resistor in series relation with the operating coil of :the relay 31 to perform a similar function for the relay 31.

{Contact member a of the relay 38A is effective in its picked-up or upper position to cut a corresponding resistor 40 in series relation with the operating coil of the relay 38 for a similar purpose. I

As in the embodiment of Fig. 1, resistors 4| are out into series relation with the coil of the relays 36 and 31 by the contact members b of the relays 31 and 38, respectively. It should be understood that when both resistors 49 and II are cut into series relation with the coil of either of the relays 36 or 31, the impressed voltage is sufiicient to maintain the relays picked-up.

It will benoted, however, that when the speed of the car reduces to the drop-out point of the relays 31 and 36, the resistors III-have already been cut out of the circuit due to the previous drop-out of relays 31 and 38 respectively so that, .at such time, only the resistors 40 are in series relation with the coils of the relays.

Since the operation of the embodiment shown in Fig. 3 is the same as that of the embodiment of Fig. 1 except as pointed out above, it is believed unnecessary to further describe the operation of the embodiment shown in Fig. 3.

Embodiment shown in Fig. 4

. The embodiment shown in Fig. 4 is the same as thatshown in Fig. 1 except that a solenoidoperated selector switch I I 5, responsiv to the voltage across the brush terminals of the generator 35 associated with the leading axle of the front wheel truck II, and three conventionalrelays II 6 and H1 and II 8 of the neutral type are substituted for the relays 36, 31, and 38 of Fig. 1.

In view of th fact that the major portion of the. embodiment shown in Fig. 4 duplicates that in Fig. 1, only that portion of theembodiment of Fig. 4 is shown which makes clear the difierent structure and character of operation.

The solenoid-operated selector switch I I 5 comprises, as shown in diagrammatically in Fig. 4, a. tubular casing in which is contained a solenoid winding I2I for operating a plunger I22 of magnetic material. The plunger I22 is pivotally connected to one end of a pivoted switch arm I23 and pivotally shifts the arm I23 to different positions in accordance with the movement and position of the plunger.

The solenoid winding I 2I has its terminals connected, by the wires. 20 and .30, across the brush terminals of the generator 35 associated with the leading axle of the front wheel truck II. A reversing switch I24 is interposed in the wires 20 and 36 in such a manner as to enable the operator to reverse the connections of the winding 'I2I upon a reversal of directionof travel of the car to insure unidirectional flow of current through thesolenoid winding notwithstanding a reversal of direction of travel of the car.

The solenoid winding I2I is efiective to set up a magnetic field which urges the plunger I22 in the left-hand direction against the. opposing force of a coil spring I25. The amount ofmovement of the plunger I22 from its normal righthand position shown is substantially proportional to the degree of energization of the solenoid winding which is in turn proportional to the voltage impressed on the winding by the generator 35.

It will thus be seen that the switch arm I23'is pivotally rocked into difierent positions in accordance with the speed of travel of the car.

The switch arm I23 has in insulated relation thereon a contact tip I26 which is adapted to engage in wiping contact four contact segments I21, I28, I29, and I30. These contact segments are of such width in relation to the 'arcuate or pivotal movement of the contact tip I26 that the contact tip I26 remains in engagement with the contact segments only over certain ranges of speed. As long as the car is stopped or does not exceed a speed such-as, for example, 20 M. P. H., the contact tip engages'only the contact segment I21. When the speed of the car exceeds 20 M. P. H., the contact tip I26 runs off the contact segment I21 and engages contact segment I28. As long as the speed of the car remains above 20 M. P. and below a certain higher speed such as 40 M. P. H., the contact tip I26 engages only the contact segment I 28. When the speed of the car exceeds 40 M. P. H., the contact tip- I26 runs off segment I23 and engages the contact segment I29. As the speed of travel of the car increases'above 40 M. P. H., the contact tip I26 moves over the face of the contact segment I29 towardthe contact segment I 30. When the speed of the car exceeds 65 M. P. H., the contact tip I26 engages the contact segment I 39. As the speed of the car increases above 65 M. P. H., the contact tip I26 shifts so as to completely disengage the contact segment I29 and engage only the contact segment I 39.

One correspondingterminal of the operating coil of the several relays H6, I I1, and H8 is connected by wires I36, I31, and I38 to the contact segments I21, I 29, and I36, respectively, of the solenoid-operated selector switch I I5. The opposite terminals of the operating coils of the relays I I6, I I1 and I I8 are connected to a common wire I39 which is a'branch of the wire connected to the positive terminal of the battery TI. The pressure-operated switch 26 is interposed in the wire 95 between the point of connection of the wire I 39 and the positive terminal of the battery 1I. 5

Switch 13 is interposed in the wire I39 between the point of connection of the wire I39 to the wire 95 and the terminals of the operating coil of the It willaccordingly be seen that with the pressure switch 26' in its closed position corresponding to application of the .brakes and with the switch 13 in closedposition, the solenoid-operated selector switch I I5 is effective to selectively complete circuits for energizing. the operating coils of the relays IIB, Ill, and ll8kdepending uponthe engagement of the contacttip I26 with the corresponding contact segment I21, I29' or I35 respectively.

Each of the two relays 'I I5 and Ill has a single front-contact member which is actuated to closed position from an open position upon energization of the relay coil. The relay II 8", however, has two front-contact members designated a and b respectively.

The contact members of the relays II 6 and Ill andthe contact member a of the relay II 8 are effective in their closed positions'to connect the terminal wires I4, I8 and BI of the low magnet valve 56; the medium magnet valve 55, and the high magnet valve 54, respectively, of the speed-controlled valve mechanism 24 to a branch wire I42 of the wire I39. The wire I42 is connected to the wire I39 at a point between the switch I3 and the operating coils of the relays IIS, III,andII8.

The contactmember b of the relay I I8 is effective in its closed position to connect the wire I42'to the terminal wire 18 of the medium magnet valve 55. Thus, when the contact tip I26 engages only the contact'segment I30, as it does at vehicle speeds above 65M. P. H., the energizing circuit ofthe magnet winding of the medium magnet valve piston 55 remains closed through the closed'contact member bof the relay H3,

although relay II'I is'dropped-out.

Thus it will'be seen that the same cycle of energization of the magnet valves 56; 55, and 54 of theispeed-controlled valve mechanism 24 is effected upon increasing and decreasing speeds as in the-embodiment shown in Fig. 1.

In the embodiment shown in Fig; 4, the switch I3 is effective, when pened, to prevent the energization of the operating coils of the relays H6. H1, and H8 as well as the energization of the magnet windings of" the magnet valves 54, 55, and 53' of the speed-controlled valve mechanism 24. Thus the switch I3 functions, as in Fig. 1, to condition the speed-controlled valve mechanism 245 as to establish a pressure in the brake cylinders which is one-half the pressure established in the control pipe in the event of failure of the [generator 35to energize the solenoid winding IZI o'f'the solenoid-operated selector switch H.

By arranging the switch 95 in the manner indicated in Fig. 4, the operation of the sanding magnet valve 32 and of the magnet valve device 55- of the slip-controlled valve mechanisms 25 may be prevented, upon opening of switch 95, without interfering with the control of the magnet valves of the speed-controlled valve mecharliism 24'by the solenoid operated selector switch I. 5.

Embodiment shown in Fig. 5

The embodiment shown in Fig. 5 is the same as that in Fig. 1 except as shown fragmentally, two so-called torque relays I and I46 and three neutral type relays IISA, WM, and NBA are provided in place of the voltage-responsive relays 36, 3?, and 38 of Fig. 1.

As shown diagrammatically in Fig. 5, the torque relay I45 comprises a pair'of-stationary pole pieces I41 on each of which is a field winding I48, and a rotor having a bipolar element I49 of magnetic material which is carried on a rotary spindle I5I mounted in suitable journal bearings not shown. Fixed to the spindle I5I is a contact arm I52 havingan outer insulated contact tip I53 for selectively engaging. either of two stationary spaced contact members I53 and I54 carried in insulated relation on a stationary. base I563. The spindle I5I is biased rotarily by a torsion spring I5? to a normal position in which the contact tip I53 engages the contact member I54.

The two field windings I48 are connectedin series relation to each other across the output terminals of a full-wave rectifier. I59, illustrated relay I45.

as of the copper-oxide disk type. The input terminals of the rectifier I59 are connected by the wires. 20 and 33 respectively across the brush terminals of the generator 35 associated with the leading axle of the front wheel truck II. The arrangement of the field windings I48 is Such as to produce opposite magnetic poles at the gap between the pole pieces I41 so that the magnetic flows across the gap between the pole pieces The torque relay I46 is similar to the relay I45 but diiiers therefrom in that the contact arm I52 thereof moves through a Wider arc than does the contact arm of relay I45, between a stop I65, defining the normal position, and a contactmember I6I. The field windings I48 of. the relay I46 are connected in series; relation to each other across the output terminals. of the rectifier J59 in parallel relation to the field windings of the Like windings I48 of relay I 45, they produce opposite magnetic poles at the gapbetween the pole pieces I41.

The arrangement. of the contact arm I52 and the associated contact members I54 and I55 or I6! of the torque relays is such that as long as the car is stopped or travels at a speed less than 20 M. P. H., the voltage impressed on the field windings of the torque relays is ineffective to cause rotary movement of the spindles I5I and consequently shifting of the contact arms I 52 out of their normal positions.

When the speed of the car increases above 20 M. P. H., the generator voltage impressed on the field windings of the torque relays is such as to initiate a rotary movement of the spindles I5I causing displacement of the contact arms I52 in further movement of the contact arm I52 of the torque relay I45 is prevented,the contact tip I53 on the arm I52 being however more firmly pressed into contact with the contact member I55.

As the speed of the car continues to increase above 40 M. P. the contact arm I62 of the torque relay I46 continues to move toward the contact member I6I and, when the car exceeds a speed such as 65 M. P. H., the contact tip I53 on the arm I52 engages the contact member IBI. As thespeed of the car continues to increase above 65 M. P. H., further movement of the contact arm is prevented although the contact tip is more firmly pressed into engagement with the contact member.

Conversely, when the speed of the car reduces below 65 M. P. H., the contact tip on the arm I 52 of the torqu relay I46 disengages the contact member IBI. Similarly, the contact tip on the arm.l52 of the torque relay I 45 disengages the contact member I55 when the speed of the car decreases below 40 M. P. H. When the speed of the car reduces below 20 M. P. 1-1., the contact tip I53 on the arm I52 of each relay reengages the contact member I54 or stop I60 and remains in engagement therewith as the speed of the car reduces thereafter to zero speed.

The construction of the torque relays I 45 and I46 is such as to require flow of current through the field coils I48 thereof in one direction only in order to effect the operational movement of the contact arms I52 out of the normal position thereof upon the increase of voltage impressed thereon. Rectifier I59 is accordingly provided in order to insure the proper direction of flow of current through the field coils I48 of the torque relays regardless of the direction of travel of the car and, consequently, of the polarity of the brush terminals of the generator 35 supplying voltage to energize the field coils. If desired, a reversing switch, such as the reversing switch I24 employed in the embodiment shown in Fig. 4, may be provided in place of the rectifier I59. The rectifier I59 is inherently automatic in character whereas the reversing switch requires or some other automatic operating means not a part of this invention. I

One corresponding terminal of the operating coil of each of the relays IIBA, lIIA and BA is connected by the wires I36, I31 and I38 to the contact members I54, I55 and NH, respectively, of the torque relays. of the operating coils of these relays are connected by a common wire I39 to the negative terminal of an auxiliary battery Ila. The contact tip I 53 on the contact arms I 52 of each of the torque relays I45 and I46 is connected by a wire I63 to the positive terminal of the battery Ila.

A pressure switch 26A is provided in Fig. 5 which differs from the pressure switch 26 of previous embodiments in that it has two insulated contact members a and 1) instead of but one con tact member. The contact member a correponds to the single contact member of the pressure switch 25 and controls the circuit through the wire 95 in the same manner as in previous embodiments. The contact-member b of the pressure switch 26A controls the circuit through the wire I39 so as to interrupt the energizing circuit for the coils of the relays IIBA, I HA and IIBA, subsequently to be described, unless the control pipe I8 is charged to a sufiicient pressure.

An auxiliary switch 13a, indicated as of the manual operation The remaining terminals knife type, is also included in the wire I39 so that when opened it prevents energization of the coils of the relays IIBA, IIIAand IIBA independently of the pressure switch 25A.

In operation, it will be apparent that with the contact tip I53 on the contact arm I52 of the torque relay I45 engaging the contact member I54, with the contact member I) of the pressure switch 25A in closed position, and with the switch 130, in closed position, a circuit is completed for energizing the operating coil of the relay IIGA. In a similar manner, with the contact tip I53 on the arm I52 of the torque relay I45 engaging the contact member I55 a circuit is completed for energizing the operating coil of the relay IIIA. Similarly, with the contact tip I53 on the arm I52 oi the torque relay I46 engaging the contact member IBI, a circuit is completed for energizing the operating coil of the relay II8A.

The auxiliary battery He is of relatively low voltage compared to the battery II so that the current in the energizing circuit of the relays IISA, II'IA and I ISA interrupted by disengagement of the contact tips on the arms I52 of the torque relays from the associated contact members I54, I55 or NH is not such as to cause excessive burning or pitting of the contact members and of the contact tips which might occur if the full voltage of the battery II were employed. Obviously, the coils of the relays I ISA, IIlA and IIBA are suitably designed so as to pick-up the single contact members thereof upon the completion of the energizing circuit therefor.

The contact members of the relays IIBA, TA and IIBA are arranged to control the energizing circuits of the magnet valves 56, 55 and 54 respectively of the speed-controlled valve mechanism 24 in a manner similar to that of the contact members of the relays IIS, II! and H8 of the embodiment shown in Fig. 4. It will be noted, however, that since the contact tip I53 of the torque relay I45 remains in engagement with the contact member I55 as long as the speed of the car exceeds 40 M. P. 1-1., it is unnecessary to provide the relay I I8A with an additional contact member corresponding to the contact member b of the relay H8- It will be apparent that the magnet valves 54, 55 and 55 of the speed-controlled valve mechanism 24 are thus selectively energized or deenergized in difierent combinations depending upon the speed of the car or train in exactly the same manner as in the previous embodiments. It will also be apparent that the pressure switch 25A of the embodiment shown in Fig. 5 prevents energization of the relays I'IBA, TA and NBA and of the magnet valves of the speed-controlled valve mechanism 24 until an application of the brakes is initiated, thus preventing undesired drainage of current from the batteries II and Taken together with the description of the op eration of the embodiment shown in Fig. 1, it believed that the above description sufliciently describes the operation of the embodiment shown in Fig. 5 and accordingly no further description is believed necessary.

Summary Summarizing, it will be seen that we have disclosed a plurality of embodiments of a brake and sanding control equipment whereby the de-, gree of application of the brakes is automatically reduced as the speed of a car or train reduces and whereby, upon slipping of an individual wheel or pair of wheels during application of the brakes, the brakes associated with the Wheel truck having the slipping wheels are automatically rapidly released and sanding of the rails effected to prevent sliding of these wheels.

- :In all embodiments, each axle is provided with a dire-ct current generator driven at a corresponding speed and supplying a voltage corresponding to the speed of rotation of the individual axle and Wheels fixed thereto. In all embodiments, electrical apparatus responsive to the'rate of reduction of the corresponding generator= voltage is effective to initiate a sandin operation and the rapid release of the brakes to prevent sliding of the wheels.

1 linall of the embodiments, the voltage of one of the axle-driven generators is adapted tocontrol various types of apparatus for causing a reduction in the degree of application of the brakes as the speed of the car or train reduces.

Inthe first embodiment, a plurality of voltage-responsive relays respectively operative at different critical voltages corresponding to different vehicle speeds is employed to control the degree of application of the brakes and effect a reduction in the degree of application automatically as the speed of the car reduces.

A second embodiment discloses a modification of the. first embodiment for insuring pick-up and drop out'of the voltage-responsive relays at substantially the same speed regardless of whether the speed is increasing or decreasing. A third embodiment discloses a solenoid-operated selector switch controlled responsively according to the voltage of one of the axle-driven generators for controlling the degree of application of th brakes and eiiecting a reduction therein. automatically as the speed of the car reduces. Another embodiment discloses an arrangement including so-called torque relays operatively responsive according to the voltage of one of the axle-driven generators for controlling the degree of application of the brakes and the automatic reduction in the degree of application as the speed of the car reduces.

While we have shown and described only several embodiments ofour invention, it Will be apparent that various omissions, additions, or modifications may be made in the embodiments shownwithout departing from the spirit of our invention; It is accordingly not our intention to limit the scope of our invention except as it is necessitated by the scope of the prior art.

Having now described our invention, what we claim as new and desire to secure by Letters Patent, is:

'1. Brake control apparatus for a wheeled vehicle comprising, in combination, means for causing application and release of the brakes associated with the wheels of the vehicle, means for producing an electrical effect substantially proportional in degree to the speed of rotation of a vehicle wheel, means controlled according to the degree of electrical effect supplied by said producing means for controlling the degree of application of the brakes on said wheel, and means controlled according to the rate of change in the degree of electrical efiect sup-plied by said producing means for also controlling the degree of application of the brakes on said Wheel.

, 2. Brake control apparatus for a wheeled vehicle comprising, in combination, means for causing application and release of the brakes associated with the wheels of the: vehicle, means for producing a voltage substantially proportional to the speed of rotation of a vehicle wheel, means controlled according to the voltage supplied by said producing means for controlling the degree of application of the brakes on said wheel, and means controlled according to the rate of change of voltage supplied by said producing means for also controlling the degree of application of the brakes on said wheel.

3. Brake control apparatus for a wheeled ve-.

hicle comprising, in combination, means. for causing application and release of the brakes as-.- sociated with the wheels of thevehicle, means for producing an electrical efiect substantially;

proportional in degree to the speed'of rotation of a vehicle wheel, means controlled according to'the degree of electrical effect supplied by said producing means and effective during an application of the brakes for automatically reducing the degree of application of the brakes on all the braked wheels of the vehicle as the speed of rotation of the vehicle wheel reduces, and means operative in response to a reductionin the degree of electrical effect supplied by said producing means at a rate exceeding a certain rate for causing a rapid reduction in the degree of application of the brakes on only certain of the braked wheels and including said one wheel.

4; Brake control apparatus for a wheeled vehicle comprising, in combination, means for causing application and release of the brakes associated with the wheels of the vehicle, means for the degree of application of the brakes associated with only certain of the'braked Wheels including said one wheel.

5. Brake control apparatus for a vehicle having a plurality of separately rotatable wheels'coi'nprising, in combination, means for effecting application and release of the brakes associated with all of said wheels, individual means associated with each of said wheels respectively for producing an electrical effect substantially proportional in degree to the speed of rotation of the corresponding wheel, means controlled according to the degree of electrical efiect supplied by one of said producing means for controlling the degree of application of the brakes on all of said wheels, means responsive to a change in the electrical effect supplied by any one of certain ones of said producing means at a rate exceeding a certain rate forcontrolling the degree of application of the brakes associated with the corresponding wheels, and additional means responsive to a change in the electrical efiect supplied by any one of other certain ones of said producing means at a. rate exceeding said certain, rate for controlling the degree of application of the brakes on the corresponding wheels.

6. Brake control apparatus for a wheeled vehicle, comprising, in combination, a normally uncharged control pipe chargeable with fluid at different pressures, a variably conditionable relay valve mechanism adapted to supply fluid at a pressure having any one of a plurality of different ratios to the pressure established in said pipe depending upon the condition thereof for eifecting a corresponding degree of application of the brakes, means for producing a voltage substantially proportional to the speed of rotation of a vehicle wheel, voltage-responsive means effective according to the voltage supplied by said producing means for varying the condition of said relay valve mechanism upon changes in the speed of rotationof said wheel, whereby to cause a variation of the pressure supplied by said relay valve mechanism and the consequent variation in the degree of application of the brakes, means operative in response to a change in the voltage supplied by said producing means at a rate exceeding a certain rate, and means controlled by the last said means for effecting a rapid reduction in the degree of the application of the brakes associated with said wheel.

7. Brake control apparatus for a wheeled vehicle comprising, in combination, a brake cylinder operative to cause application and release of the brakes associated with a vehicle wheelin accordance with the pressure of the fluid supplied thereto, a relay valve device operative to cause the establishment of pressure in said brake cylinder in accordance with the pressure of an operating fluid supplied to said relay valve device, means controlled according to the rotative speed of the said vehicle wheel effective during an application of the brakes for eifecting repeated reductions of limited duration in the pressure of the fluid supplied to said relay valve device as the speed of rotation of the vehicle wheel diminishes, and means effective only when the vehicle wheel decelerates at a rate exceeding a certain rate for effecting a single rapid reduction of the operating pressure supplied to said relay Valve device to below a certain pressure to effect a corresponding rapid reduction of the pressure in the brake cylinder.

8. Brake control apparatus for a wheeled vehiclecomprising, in combination, a brake cylinder operative to cause application and release of the brakes associated with a vehicle wheel in accordance with the pressure of the fluid suppliedthereto, a relay valve device operativeto cause the establishment of pressure in said brake cylinder in accordance with the pressure of an operating fluid supplied to said relay valve device, means controlled according to th rotative speed of the said vehicle wheel effective during an application of the brakes for effecting repeated reductions of limited duration in the pressure of the fluid supplied to said relay valve device as the speed of rotation of the vehicle wheel diminishes, means effective only when the vehicle wheel decelerates at a rate exceeding a certain rate for effecting a single rapid reduction of the operating pressure supplied to said relay valve device to below a certain pressure to effect a corresponding rapid reduction of the pressure in the brake cylinder, and means e-fiective when the pressure in the brake cylinder reduces below said certain pressure for causing the last said means to terminate the reduction of the operating pressure for the said relay valve device and initiate a resupply of fluid thereto at a pressure controlled by said speed-controlled means.

9. Brake apparatus for a wheeled vehicle comprising, in combination, brake means associated with a, wheel of the vehicle, means including a plurality of electroresponsive means adapted to be selectively energized ordeenergized in differ ent combinations, said means being effective to cause application of the brake means with dif ferent degrees of force depending upon the combination of the electro-responsive means in effect, means for supplying a voltage substantially proportional to the speed of rotation of the said wheel, and means responsive to the voltage delivered by said voltage-supply means for selectively controlling energization and deenergization of the said plurality of electroresponsive means so as to vary the combination in effect and thereby vary the degree of application of the brakes as the speed of rotation of said wheel varies.

10. Brake control apparatus for a wheeled vehicl comprising, in combination, a brake cylinder adapted to apply the brakes associated with a vehicle wheel with varying force corresponding to the pressure of the operating fluid supplied thereto, a normally uncharged pipe chargeable with fluid at different pressures, relay valve means including a plurality of electroresponsive means adapted to be energized or deenergized in different selected combinations whereby said relay valve means is effective in response to a given pressure established in said pipe to establish in said brake cylinder any one of a plurality of different pressures dependent upon the combination of the electroresponsive means in effect,

means for supplying a voltage substantially pro-' portional to the speed of rotation of the said vehicle wheel, and means operatively responsive to the voltage delivered by said voltage-supply means for selectively controlling energization and, deenergization of the electroresponsive means of said relay valve meansso as to vary the combination in effect whereby said relay valve means is operated to vary thepressure in the brake cylinder automatically without any change in the pressure in said pipe as the speed of the said vehicle wheel varies.

11. Brake control apparatus for a wheeled vehicle comprising, in combination, brake means associated with a wheel of the vehicle, meansineluding a plurality of electroresponsive means adapted to be energized and deenergized in different selected combinations whereby said means causes application of the brake means with any one of a plurality of different degrees of force dependent upon the combination of the electroresponsive means in effect, means for supplying a voltage substantially proportional to the speed of rotation of the vehicle wheel, a plurality of voltage-responsive relays on which the voltage delivered by said voltage-supply means is impressed, one of said voltage-responsive relays being operatively responsive only to a voltagein excess of a certain value, a second one of said relays being operatively responsive only to a voltage in excess of a second certain value higher than the first said ce'rtainvalue, and a third one of said relays being operatively responsive only to a voltage in excess of a third certain value higher than said second voltage, each of said relays being effective to control energization and deenergization of a corresponding one of said plurality of electroresponsive means whereby to automatically vary the combination of electroresponsive means in effect in accordance with the speed of rotation of the said wheel. 7

l2. Brake control apparatus for a wheeled ve-' hicle comprising, in combination, brake means associated with a wheel of the vehicle, means including a plurality of electroresponsive means adapted to be energized and deenergized in different selected combinations whereby said means lays being operatively responsive only to a voltage in excess ofa second certain value higherthan the first said certain value, a third one of said relays being operatively responsive only to a voltage in excess of a third certain value higher than said second voltage, each of said relays being effective to control energization and deenergization of a corresponding one of said plurality of electroresponsive means whereby to automatically vary the combination of electroresponsive means .in elfect in accordance with the speed of rotation of the said wheel, current-limiting means associated with said one relay, a second current-limiting means associated with said second relay, said second relay being effective to render the first said'current-limiting means effective to limit the current through the first said relay when it operatively responds to a voltage in excess of said second certain value, and said third relay ,being adapted to render said second current-limiting means effective to limit the current through said second relay when said third relay operatively responds to a voltage in excess of said'thirdvalue. 1

13. Brake control apparatus for a Wheeled vehicle comprising, in combination, brake means associated with a wheel of the vehicle, means including a plurality of electroresponsive means adapted to be energized and deenergized in different selected combinations whereby said means causes application-of the brake means with any one of .a plurality-of different degrees of force dependent upon the combination of the electror'esponsive means effect, means for supplying a voltage substantially proportional to the speed of rotation of the vehicle wheel, a plurality of voltage-responsive relays on which the voltage delivered icy-said voltage supply means is impressed, one-of said voltage responsive relays being-loperatively responsive only to a voltage in excess of 'alcertain value, a second one of said relays loeingoperatively responsive only-to a voltage in :ex'cess'of a second certain value higher than the first said certain value, a third one'of said relays being operatively responsive only to a voltage in excess of a third certain value higher than said second voltage, each of said relays being effective to control :energization and -deene=rgization of a corresponding one of said plurality of 'electroresponsive 7 means whereby to automatically .vary the combination of electroresponsive means in effect accordance with the speed of rotationof the said wheel, current-limiting means associated with ,said" one rela a second current-limiting means associated with said second'relay, saidsecond relay beingeffective to render the fiIISt said current-limiting means effective to limit the current through the first said relay Whenit operatively responds to a voltage in excess of said second certain value, :said third relay being adapted to render said second currentlimiting means effective to limit the current through said second relay when said third relay operatively responds to a voltage in excess of said third value, and means effective upon the operative response of eachlof said relays to an increasing voltage for rendering said one, said second, and said third relays thereafter opera: tively responsive to a reducingvoltage at values corresponding substantially to said first certain, said second certain, and said third certain voltages, respectively.

14. Brake control apparatus for .a wheeled'veh-icle comprising, in combination, brake means for a wheel of the vehicle, means including a plurality of electroresponsivemeans adapted to be energized and deenergized in different selected combinations to cause said means to effect application of the brake means with different degrees of force dependingupon the combination of electroresponsive means in effect, means for supplying a voltage proportional to the speed of rotation of the said vehicle wheel, a pluralityof voltage-responsive relays corresponding in number to the n-umberof the electroresponsive means, said voltage-responsive relays'being operatively responsive in succession to different successively higher voltages as the voltage impressed thereon increases and effective respectively to control energization and deenergization of a corresponding one of said electroresponsive means, and means effective upon the operative response of said voltage-responsive relays to cause a reduction of the voltage impressed on the preceding relay whereby to prevent the imposition of excessive voltage on said relay.

15. Brake control apparatus for a wheeled vehicle comprising, in combination, brake means for a wheel of the vehicle, "means including'a plurality of electroresponsive means adapted to be energized and deenergized in different selected combinations to cause said means to effect application of the brake means with different degrees of force depending upon the combination of electroresponsive means in effect, means for supplying a voltage proportional to the speed of rotation'of the said vehicle wheel, a plurality of voltage-responsive relays corresponding in number to the number of the electroresponsive means; said voltage-responsive relays being operatively responsive in succession to different successively higher voltages as the voltage impressed thereon increases and effective respectively to control energization and deener gization of a corresponding one i of said electroresponsive means; and" means effective upon the operative response of each of said relays to an increasing voltage for rendering said relay ,operatively responsive to substantially the same voltage when the voltage impressed thereon decreases.

16. Brake control apparatus for a wheeled ve hic'le comprising, in combinatiombrake means for a wheel of the vehicle means including a plurai ity of electroresponsi-ve means adapted tobeenergized or .deenergized in different selected com'binations'to cause'said' means to effect ap plication of the brakes with different degrees of force corresponding tothe combination of elec troresponsive means in effect, means for supplying a voltage substantially proportional to-the speed of rotation of the'said-vehi'cle wheel, an'la selector switch having a solenoidwinding'which is energized in varying degree according to "the voltage deliveredby-said voltagesupply means, and a switch element which is operated to a plurality of different positions depending'upon' the degree of nergization-of said solenoid wi-nd ing, the switchelementof the sa-idselectorswitoli being efiectivein its differentposi-tions to selectively control energization and deenergization of the said plurality of electroresponsive means whereby the degree of application of the brake means is varied upon variations in the speed of the vehicle wheel.

17. Brake control apparatus for a Wheeled Vehicle comprising, in combination, brake means for a wheel of the vehicle, means including a plurality of electroresponsive means adapted to be energized or deenergized in different selected combinations to cause said means to effect application of said brake means with different degrees of force depending upon the combination of the electroresponsive means in effect, means for supplying a direct-current voltage substantially proportional to the speed of rotation of the vehicle wheel and of opposite polarity depending upon the direction of rotation of said wheel, a selector switch having a solenoid winding, and a switch which is operated to any one of a plurality of different positions corresponding to the degree of energization of said solenoid winding, a reversing switch controlling the imposition of the voltage delivered by said voltage-supply means on said solenoid means in a manner to cause the polarity of the voltage impressed on the solenoid winding to be the same for opposite directions of rotation of said wheel, the switch element on said selector switch being effective in its difierent positions to selectively energize or deenergize the plurality of electroresponsive means in different combinations whereby the said brake control means effects application of the brake means to different degrees depending upon the rotative speed of the vehicle wheel.

18. Brake control apparatus for a wheeled vehicle comprising, in combination, brake means for aiwheel of the vehicle, means including a plurality of electroresponsive means adapted to be energized or deenergized in different selected combinations to cause said means to effect application of the brake means with different degrees of force depending upon the combination of the electroresponsive means in effect, means for supplying a voltage substantially proportional to the speed of rotation of the vehicle wheel, and a pair of voltage-responsive relays, each of said relays having a winding on which the voltage delivered by the voltage supply means is impressed and a switch arm which is shiftable rotarily to different positions in accordance with the degree of the voltage impressed on the windings, the switch arm of one of said relays being effective in accordance with the poistion thereof to selectively control the energizationand deenergization of two of said electroresponsive means and the switch arm of the other of said relays being effective in accordance with the position thereof to control energization and deenergization of another of said electroresponsive means.

19. Brake control apparatus for a wheeled vehicle comprising, in combination, brake means for a wheel of the vehicle, means including a plurality of electroresponsive means adapted to be energized or deenergized in difierent selected combinations to cause said means to effect application of the brake means with different degrees of force depending upon the combination of the electroresponsive means in effect, means for supplying a voltage substantially proportional to the speed of rotation of the vehicle wheel, a pair of voltage-responsive relays, each of said relays having a Winding on which the voltage delivered by the voltage supply means is impressed and a switch arm which is shiftable rotarily to different positions in accordance with the degree of the voltage impressed on the windings, the switch arm of one of said relays being effective in accordance with the poistion thereof to selectively control the energization and deenergization of two of said electroresponsive means and the switch arm of the other of said relays being effective in accordance with the position thereof to control energization and deenergization of another of said electroresponsive means, and a fullwave rectifier having the voltage delivered by said voltage supply means impressed on the input terminals thereof and adapted to have the voltage at the output terminals thereof impressed on the windings of said relays so that the windings of said relays are energized by a voltage of the same polarity notwithstanding a reversal of direction of rotation of the vehicle wheel.

DONALD L. MGNEAL. JOHN CANETTA. 

